Analytical photogrammetry

The analytical photogrammetry is a modern expression of photogrammetry , which was developed in the 1980s for practical application. It can be described as the counterpart to classic analog photogrammetry , in which the photographic measurement images are evaluated by mechanical constructions (precise levers etc.) or by optical projection methods.

Analytical photogrammetry therefore comprises the analytical description of photogrammetric methods and works with purely digital computing methods in order to determine the coordinates of the depicted object points from photogrammetric image coordinates . What happens in analog photogrammetry through optical-mechanical replication of the recording situation is now done in a computational and now largely automated way.

Development steps

Essential impulses for the theoretical development of the subject were u. a. Hellmut Schmid (approx. 1950–55), based on the first ideas of Sebastian Finsterwalder in 1903. From around 1980, digital-analytical processes began to replace the analog methods that had prevailed up until then - especially because the mechanical-optical evaluation devices (A8, B8, etc.) of the companies WILD and KERN) were relatively complicated in terms of construction and function. Since the 1990s , digital evaluation methods have become the standard.

The path to purely analytical photogrammetry was also promoted by a number of special tasks that could only be solved with great effort until around 1970. This includes:

• Increasing demand for orthophotos and large-scale basemaps
• Exact optical projection of the measurement images on an object plane → first analytical orthogonal projections (WILD, 1976)
• Automation of the measurement on the photo plates and measurement images (including stereo comparator )
• Acceleration of the evaluation through the development of computers (first Zuse Z3 1941, practically feasible from ~ 1970), microprocessors
• Solution of large matrices for the adjustment of extensive networks (→ block triangulation , e.g. BHSchmid 1953).

This resulted in further automated methods: analytical stereo evaluation systems (Helava 1957), digital projectors , etc. up to today's digital aerial camera - and (photographic image): analytical stereo evaluation systems.

See also

• Digitization , remote sensing , measuring beam
• Calibration of the instrument errors
• Terrain models , geographic information systems

Web links

• Analytical methods ( Memento from March 18, 2005 in the Internet Archive ) TU Hannover, Institute for Photogrammetry and GeoInformation
• Swiss Society for Photogrammetry, Image Analysis and Remote Sensing (SGPBF)